Die casting machine



DIE CASTING MACHINE Filed Nov. 22, 1957 q i l 1 2 m3. I 2 Z INVENTDR WILLJAMJ. DURING BY M512 & M07 ATTORNEYS Patented Apr. 25, 1939 UNITED STATES PATENT OFFICE Precision Casting Company,

Inc., Syracuse,

N. Y., a corporation of New York Application November 22, 1937, Serial No. 175,871

2 Claims.

This invention relates to an improvement in a,

die casting machine in which a delivery nozzle is movable into and out of co-operative relation with the sprue opening or inlet port of a die. The 5 invention relates more particularly to a die casting machine having a sectional die member with the sprue opening or inlet port thereof arranged in the plane of separation of the die sections and wherein at least one of said die sections is mov- 1o able with respect to the other section for opening and closing the die.

In die casting machines having a die of the above mentioned type the delivery nozzle has usually been moved into direct contact with the die sections during the casting operations. The result has been that the nozzle tends to force the die sections apart due to the relatively high pressure exerted on the nozzle necessary to prevent leakage of the molten metal between the nozzle and wall of the inlet port. This separation of the die sections permits the molten metal to escape from the die cavity and is not only detrimental to casting results but is also dangerous to the operator.

The main object of this invention is to provide a die casting machine of the above mentioned class with pressure compensating means interposed between the delivery nozzle and the die, when the nozzle is in the casting position for opposing or absorbing the pressure produced on the nozzle during the casting operation whereby the die sections may be easily maintained in tight co-operative relation with each other during the ejection of the molten metal into the cavity of the die.

A more specific object of the invention is to provide a seat for the delivery nozzle of a die casting machine adapted to be engaged by said nozzle during the casting operation and which will conform to the general contour of the nozzle through out a cross sectional area thereof and thereby contribute to the length of life of the nozzle.

These and other objects pertaining to the structure and operation of my novel compensating device will more fully appear from the following description taken in conjunction with the accompanying drawing, wherein:

Figure 1 is a detail side elevation of a die casting machine embodying the various features of this invention.

Figure 2 is a longitudinal vertical sectional view of a ladle or pressure pot and the adjacent end portion of the die member associated therewith, taken substantially on line 2-2, Figure 3.

Figure 3 is a vertical sectional view through the die casting frame taken substantially on line 3-3, Figure l with the adjacent ends of the die sections and my novel pressure compensating element or nozzle plate associated therewith illus- 5 trated in elevation.

In order to illustrate my invention, I have shown a die casting machine having a ladle or pressure pot provided with a discharge or delivery nozzle and which is movable from a re- 10 tracted position in a melting pot with the nozzle submerged in the molten metal contained in the melting pot to receive the metal therefrom, to an extended position with the nozzle in operative relation with the sprue opening of the die for 15 ejecting the molten metal into the die cavity.

More specifically, the die casting machine comprises the usual frame or fire box I having a furnace chamber 2 therein. A cover plate 3 is secured by any suitable means to the upper face of the frame I and has mounted thereon a suitable melting pot 4 adapted to extend downwardly from the plate 3 into the furnace chamber 2. A die member 5 is shown mounted on the machine frame, adjacent the forward end of the melting pot t.

The die 5 is a sectional member having the lower section as 5, thereof mounted upon the frame I and which may be removably secured to said frame by any suitable means as bolt 6 whereby said die section may be maintained in fixed predetermined relation with the melting pot 4 and frame I. The other die section, as 5", is mounted for movement into and out of engagement with the lower die section 5' for opening and closing r the die. Any suitable means may be connected with the die section 5", as an operating member or carriage indicated at l, for producing vertical movement of the die section 5" with respect to the die section 5'. The die is provided with a 40 sprue opening or inlet port 8 formed by slots or grooves 8' and 8 in adjacent faces of the die sections 5 and 5" respectively at the ends of said sections adjacent the melting pot 4, said inlet opening being in communication with the cavity 9 of the die.

The ladle or pressurepot H3, in this instance is of the goose neck type and is provided with a ver tically disposed major portion H having a pressure chamber l2 therein. A spout or goose neck 0 l3 extends from the lower end of the portion II and has secured to the outer forward end thereof a delivery nozzle 14 which is in communication with the pressure chamber I2.

A bracket I5 is secured by bolts I! to the upper portion of the delivery pot it to extend forwardly from the major portion ii of the pot. The bracket it has secured to the forward end thereof a horizontally disposed shaft i8 which extends outwardly at either end from the bracket i6 through guide slots it provided in a pair of opposite vertically extending platesfil which are made integral with or secured to the upper surface of the frame 1 at opposite sides of the melting pot 4 and near the forward end thereof.

The guide slots IS, in this instance, are each composed of a horizontal portion 13' disposed in a plane above the lower die section 5 and a vertical disposed portion l3 which extends downwardly from the rear end of the horizontal portion l9 thereby forming the inverted L-shaped slot 13 for guiding the pressure pot from the casting position to the charging position and vice versa. In this instance, the width of each slot i9 is greater than the diameter of the adjacent ends of the shaft It so that a roller, not shown, may be rotatably mounted on each outer end of the shaft i3 and which is adapted to travel in a respective slot iii to effect the easy movement of the shaft through said slot.

The shaft is is moved through the slots [8 by means of a pair of rock arms 23, positioned at the outer sides of the plates 26. The arms 23 are journaled for pivotal movement on respective shafts it, said shafts being secured to the lower portion of the respective plates 26 near the forward end thereof so that when the shaft I3 is positioned in the forward portion of the guide slots it to bring the pressure pot into the casting position, the rock arms 23 will extend substantially vertically.

The rock arms 23 may be operated by any suitable means, as for instance, a cross head, not shown, slidably mounted upon a suitable guide secured to a convenient portion of the machine, also not shown, the cross head being connected to the arms 23 by a pair of drive rods 26. Each rod 26 is pivotally secured at its rear end, as at 2?, to the lower end of a corresponding rock arm 28, secured at the upper end thereof to a respective arm 23.

The upper ends of the rock arms 23 are each provided with an elongated slot 38 through which the outer ends of the shaft it extends. The width of the slots 3%, as shown, are greater than the diameter of the shaft i8 so as to receive therein rollers, not shown, rotatably mounted on the ends of the shaft it. The rollers mounted on the ends of shaft iii which travel in the slots it and 3d provided in the plates 20 and arms 23 may be maintained on the shaft by any suitable means as by collars 3i secured to respective ends of the shaft.

The pressure pot itis maintained against undue rocking movement about the axis of the shaft i8 means of a guide rod 32 which is secured to the rear portion of a bracket i6 and extends rearwardly therefrom with the rear end of said guide rod slidably mounted in a pivotal arm 33 secured to a rock shaft 33 mounted in a bracket 35 secured to the cover plate 3. The rock shaft 35 is provided with a passageway or duct 36 which extends from one of the outer ends thereof inwardly and then upwardly through the arm 33 into registration with a passageway or bore 3'! provided in the guide rod 32 and which extends froin the arm 33 to the forward end of the rod. The forward end of the passageway 3'! is maintained in communication with the pressure chamber l2 of the pot ll! by a duct 38 provided in the rear portion of the bracket l6, as shown in Figure 2, so that when the pressure pot is in the casting position, the fluid as air under pressure may be admitted through the shaft 34, passages 36 and 31, and duct 38 to the pressure chamber l2 for discharging the molten metal contained in said chamber through the delivery nozzle l4 into the die 5.

The passage 36 in the shaft 34 and arm 33 may be connected with any suitable source of fluid pressure such as a pump, not shown, by a suitable conduit 39 which may or may not be provided with a suitable control valve, also not shown, for manually controlling the flow of fluid therethrough.

It will now be observed that when the pressure pot I is moved from the casting position as illustrated by full lines in Figure 2, to the charging position illustrated by broken lines in said figure, the nozzle M will be submerged in the molten metal contained in the melting pot 4 due to the pressure pot being rocked about the axis of shaft I8 during the vertical movement of said shaft in the guide slots I9 and to the pivotal action of the guide rod 32 about the axis of the shaft 34 as said guide rod is moved endwise through the arm 33. Similarly as the pressure pot i3 is moved from the charging position with the nozzle l4 submerged in the metal contained in the melting pot 4 to the casting position by the action of the arms 23 moving the shaft l8 along the guide slots IS, the nozzle !4 will be brought into operative alignment with the intake port 8 of the die as the shaft approaches the horizontal portion E9 of the guide slot by the action of the uide rod 32.

As the pressure pot is caused to continue its forward movement by the action of the arms 23 upon the shaft IS, the nozzle 14 will be brought into casting relation with port 8.

In order to compensate for the pressure exerted on the pressure pot by the arms 23 to maintain the nozzle M in seal tight contact with the die inlet opening, I have provided a nozzle plate 48 having a tapered aperture 4| provided therethrough which provides a seat for the outer or discharging end of the nozzle I4. The nozzle plate 49 is secured to the lower fixed die section 5' as by bolts 40', with the nozzle seat 4| in alignment with the inlet opening 8 of the die 5 when the die section 5" is in contact with the die section 5'. In as much as the inlet opening 8 of the die and the nozzle seat 4! of the nozzle plate 43 are in substantially the plane of separation of the die sections 5 and 5" the screws or bolts 26' are all arranged below the horizontal plane passing through the inlet opening and nozzle seat. In order, therefore, that the upper por tion of the nozzle plate 40 may be supported against springing outwardly by pressure exerted thereon during the ejection of the molten metal through the nozzle [4, into the die cavity 9 I have provided a pair of supporting blocks 42 which are connected by screws 43, or their equivalent, to the upper die section 5" adjacent the vertical sides thereof and in position to extend over corresponding side portions of the upper end of the nozzle plate. These supporting blocks 42 have the inner adjacent vertical faces thereof recessed, as at 44, for the reception of the adjacent upper end portions of the nozzle plate. These recesses 44 are formed with the wall thereof facing the outer side of the supporting block tapered from the upper end downwardly and outwardly for engagement with the upper end portion of the nozzle plate which is correspondingly tapered for wedging said upper end portion of the plate between the supporting blocks and the upper die section 5" when the die sections 5 and 5 are in casting relation with each other.

It will now be observed that in as much as the ends of the die sections 5' and 5 adjacent the melting pot A and nozzle plate are in the same vertical plane the upper end portion of the nozzle plate 40 will be maintained in contact with the upper die section 5" with sufficient pressure by the supporting blocks 42 to prevent passage of molten metal between the nozzle plate and the upper die section during the casting operation.

Furthermore it will be observed that in as much as the nozzle plate 40 is a fixed member and the pressure pot H) has a definite path of movement produced by the co-action of the shaft l8 and the guide slots IS, the nozzle M will also have a definite relation with the seat 4| during the casting operation and therefore the end of the nozzle engaging said seat will not only have a fluid tight pressure fit with the seat, but will also be maintained against excessive wear during the casting operation.

Although the construction and operation of the device shown and described are particularly simple and efficient, I do not wish to be limited to the exact detail shown as various changes may be made therein without departing from the spirit of the invention as set forth in the appended claims.

I claim:

1. In a die casting machine having a die composed of sections with at least one of said sections movable toward and from another section to open and close the die, said die being provided with an inlet port in the plane of separation of said sections, in combination, an apertured nozzle plate, means fixedly securing the nozzle plate to one of said die sections in sealing contact therewith and With the aperture in the plate in registration with the inlet port of the die, a delivery nozzle movable into pressure engagement with said plate in registration with said plate aperture when the die sections are in the closed position to discharge molten metal through the plate aperture and die inlet port into the die cavity, and separate means connected with the second die section and releasably engagable with the nozzle plate when the die is closed to maintain said plate in sealing contact with the latter die section during said discharging of the molten metal.

2. In a die casting machine having a delivery nozzle, a sectional die member having at least one section movable to open and close the die, said die being provided with a sprue opening in the plane of separation of the sections, and means for producing relative movement of the die and nozzle to bring them into and out of casting relation with each other, in combination, an aperture'd nozzle plate interposed between the nozzle and the die member, and means securing the nozzle plate to the die member in sealed relation therewith when the die is closed independently of pressure produced on said plate by the nozzle when said nozzle is in said casting relation with the die, said latter means including a holding element associated with one of the die sections adapted to be brought into and out of operative engagement with the nozzle plate during the closing and opening of the die member.

WILLIAM J. DURING. 

